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Free bet calculator

Free bet calculator for matched betting

Use this free bet calculator to work out the lay stake, exchange liability and retained profit from a stake not returned free bet. It is built for UK matched betting offers where the value comes from the promotion rather than predicting the winner.

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Matched betting · Calculator

Matched betting back and lay calculator

Use this matched betting calculator to work out your lay stake, liability, qualifying loss and profit. Choose between Normal, Free Bet (SNR) and Risk-Free modes. The maths is designed to stay consistent with companion app tracking and helps you avoid mistakes when placing back and lay bets.

Ideal for welcome offers, free bets, reloads, 2UP, and price boosts. Enter your back odds, lay odds and commission to see instant results.

Back bet

Lay bet

Show part lays

Enter a back stake, back odds and lay odds to see results.

What does a matched betting calculator do?

A matched betting calculator works out the exact lay stake needed to balance your bookmaker back bet at the exchange. It removes the maths and gives you the numbers you need to lock in small qualifying losses or guaranteed profit on free bets.

  • Calculates lay stake instantly
  • Shows your liability before you place a bet
  • Displays qualifying loss or profit
  • Supports free bets and risk-free offers
  • Handles underlay, overlay and custom stakes

Example: how to calculate a lay stake

Here is a simple example using the calculator. Say you place:

  • £10 back bet at odds of 2.00
  • Lay odds at the exchange of 2.04
  • Exchange commission 0 percent

The calculator gives a lay stake of £9.80 and shows a qualifying loss of around £0.20.

This is normal and expected during welcome offers. You lose a few pence to unlock a free bet worth much more.

Calculator FAQs

What is a lay stake?

The lay stake is the amount you place at the betting exchange to bet against your selection. The calculator works it out automatically.

What is liability?

Liability is the amount the exchange holds in case your lay bet loses. This is not your stake. The calculator shows liability for every bet.

What is a qualifying loss?

This is the small cost of placing your back and lay bets to unlock a free bet or promotion. A normal qualifying loss is 10p to 40p.

Does this calculator work for free bets?

Yes. Use the Free Bet (SNR) mode to calculate profit from free bets.

Does this work for 2UP, boosts and reloads?

Yes. The calculator supports standard and advanced modes used for 2UP, price boosts and hedging reload offers.

Want more than calculators?

Calculators help you place the bet correctly, but they do not find the offer or explain the full route. BYB Premium adds the Sign Up Cycle, the BYB oddsmatcher, reload alerts through Discord, supported PocketProfit logging links and Discord support around these tools.

View BYB PremiumLooking for an oddsmatcher?Join the BYB Discord community

More matched betting guides

If you are learning matched betting, these guides will help you understand the process, reduce mistakes and get more value from your free bets and reloads.

Back Yourself Betting calculators are built for the same staking logic you may later record in companion apps such as PocketProfit.

How free bet calculations work

Most bookmaker free bets are stake not returned, often shown as SNR. That means the free bet stake is not paid back to you if the bookmaker bet wins. The calculator adjusts for that by using the profit part of the bookmaker odds, then balancing it against the lay side at the exchange.

Lay stake and liability

The lay stake is the exchange bet against your free bet selection. Liability is the amount the exchange holds in case that lay bet loses. Higher lay odds usually mean higher liability, so checking the number before placing the bet is important.

Worked example

If you have a 10 pound SNR free bet at back odds of 5.00 and can lay at 5.20, the calculator estimates the lay stake needed to balance the outcomes. If the bookmaker bet wins, you keep the free bet profit after exchange liability. If the exchange bet wins, you keep the lay stake after commission. The aim is to retain a sensible percentage of the free bet value.

Common free bet mistakes

  • Using Normal mode instead of Free Bet mode for an SNR token.
  • Forgetting exchange commission when comparing lay odds.
  • Choosing the wrong market or runner at the exchange.
  • Ignoring liability and finding out too late that the exchange balance is too low.
  • Accepting poor retention without checking an oddsmatcher first.

Free bet calculator FAQ

What is a free bet calculator?

A free bet calculator works out the exchange lay stake and liability for a bookmaker free bet. It helps you estimate the retained profit before placing the free bet and matching lay bet.

What does SNR mean?

SNR means stake not returned. If a 10 pound free bet wins at 5.00, the bookmaker usually pays 40 pounds profit rather than returning the 10 pound free bet stake.

What is free bet liability?

Liability is the amount held by the betting exchange in case your lay bet loses. It depends on your lay stake and lay odds.

Can I use this for risk free bets?

Yes. The calculator also includes a Risk-Free mode, but most standard bookmaker free bets should be calculated in Free Bet mode.